They published their study in Current Science, showing that the treatment alters the chemical structure of the pine needles to make them accessible to microbial activity, so they can produce a high biogas yield.

Ravi Pratap Singh of Farm Machinery and Power Engineering College of Technical, GB Pant University of Agriculture and Technology, Uttarakhan, told IANS: “The bio-treated pine needles can be mixed with available cattle dung and fed to biogas plants in nearby village to generate biogas rich in methane.”

This has other benefits as well, including helping to prevent forest fires in India’s Himalayas. The pine needles cannot be eaten, do not decay as easily as other vegetation, and are highly flammable, which is why they are one of the biggest causes of forest fires.

Mr Singh added that the dry foliage also stops the soil absorbing excess water, which causes groundwater table to deplete.

Instead, however, they could be used as a useful energy source through the pre-treatment.

This could boost the amount of biogas recorded on liquid level gauges. This comes after the government’s Digest of UK Energy Statistics revealed Britain’s generation of energy from bioenergy sources grew by 30 per cent from 2014 to 2015.

It also reported anaerobic digestion generated 40 per cent more power during these 12 months, while electricity generation increased by 29 per cent.